Epicyclic gearbox

2nd July 2019

In the days before synchromesh or automatic gearboxes, it was a real challenge for a driver to match the revolutions of the engine to make sure that the final drive gear matched the revolutions of the road wheels. Often there was a lot of scraping, grunting and crashing as drivers would attempt to change gear successfully.

A far superior device was the epicyclic or ‘planetary’ gearbox where a ‘sun’ gear would have ‘planet’ gears moving in different orbits to provide different ratios which were adopted from the very first Lanchester car in 1895.

They were incredibly smooth and when Henry Ford visited the Lanchester factory, he had never seen this before and he used the design in his Model T which sold over 15 million cars.

The epicyclic gearbox combined with a fluid flywheel transmission meant the driver could select any gear and start off smoothly before selecting another gear and moving into it equally smoothly.  Demonstrator driver Archie Millership would often change from reverse to first, to third and back again to amaze potential customers.